Reduced pressure load finger seal assembly

ABSTRACT

A sealing assembly for achieving a fluid seal between a rotatable shaft and a housing circumscribing the rotatable shaft to inhibit fluid leakage therebetween a high pressure fluid region and a relatively lower pressure fluid region. The sealing assembly includes at least one primary seal, comprising an axial stack of a plurality of diaphragm members, including an upstream diaphragm and a downstream diaphragm. A plurality of finger seal plates are positioned between the upstream diaphragm and the downstream diaphragm. The plurality of diaphragm members define a passageway in fluid communication with the high pressure fluid region and a low pressure fluid region. The sealing assembly includes at least one secondary seal positioned within the passageway and configured to convert fluid from a high pressure axial pressure balance to a low pressure axial pressure balance thereby reducing a radially inward pressure load.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

This invention was made with Government support under funding programVAATE STF having Contract No. F3361503D2355 awarded by The US Air Force.The Government has certain rights in this invention.

TECHNICAL FIELD

The present invention relates to an apparatus for achieving a fluid sealbetween rotatable and static members. More particularly, the presentinvention relates to an apparatus for achieving a fluid seal between arotatable shaft and a housing circumscribing the rotatable shaft.

BACKGROUND

Sealing between rotating and static components of a gas turbine engineis an important element in minimizing fuel burn and increasing power toweight ratio. Previous attempts at providing sealing members includebrush seals wherein a plurality of elongate filaments or fibers areclustered together and secured to one of a pair of relatively movablemembers for sliding contact with another member. The resulting sealfunctions as a contact or tight-clearance seal by inhibiting fluid flowbetween the pair of relatively movable members. Prior art teaches thatthe brush seal may be made of metallic filaments or wire, for example,carried by one of the members and may be arranged as a radial or axialseal with a smooth or grooved engagement surface on the other of thepair of members.

While various types of contact or tight-clearance seals may be used inthe bearing compartment region where relative motion between rotatingand static members is small, labyrinth seals (also known as knife seals)are typically used elsewhere in the engine where larger relativedisplacements may be encountered. Labyrinth seals are well known fordurability, reasonable cost and ability to operate at high surfacespeeds and pressure drops. However, they can be prone to degradationupon rubbing during maneuvers and transient power excursions and maythus operate at clearances which can result in unacceptable leakage.

Finger seal designs have been produced in order to accommodate the largerotor displacements during maneuver and power transients whilemaintaining control of leakage. Many of the early finger seal designsencountered hysteresis problems. Subsequent finger seal designs werepressure balanced to effectively eliminate the significant hysteresisseen in the early finger seal configurations. Continuation in thedevelopment of the finger seal design has revealed deficiencies thatlimit its potential application to commercial gas turbine engines. Theaddition of the axial pressurization circuit described in U.S. Pat. No.6,196,550 by Arora to alleviate seal hysteresis had the undesirableeffect of radially loading the fingers into the rotating member. Themagnitude of loading is proportional to the differential pressure acrossthe seal.

Increasing demand on engine performance has resulted in higherdifferential pressures and increased radial finger loads. This hasresulted in high heat generation, unacceptable finger contacttemperatures and excessive, accelerated wear. As the engine transitionsto a lower differential pressure operating condition, the radiallyinward force diminishes and the fingers retract to a new equilibriumposition, leaving a clearance between the fingers and the rotatingmember. In view of the above, it is an object for this invention toprovide a reduced pressure load (RPL) finger seal that minimizesundesirable radially loading of the fingers into the rotating member.

An undesirable aspect of the reduced pressure load finger seal design isan increase in axial pressure loading. Another object of the presentinvention is to provide a reduced pressure load finger seal whichovercomes resistance to radial displacement of the fingers due to radialfriction forces induced by the increase in axial loading. Hence, thereis a need for a reduced pressure load finger seal that, in addition,provides for a reduction in axial pressure loading.

BRIEF SUMMARY

There has now been developed a sealing assembly for disposition incooperation with a body defining a bore and a shaft member rotatablyreceived in the bore, and to inhibit fluid leakage between a highpressure fluid region and a relatively lower pressure fluid region.

In a first embodiment, by way of example only, the sealing assembly iscomprised of at least one primary seal comprising an axial stack of aplurality of diaphragm members. The axial stack including an upstreamdiaphragm and a downstream diaphragm. A plurality of finger seal platesare sandwiched between the upstream diaphragm and the downstreamdiaphragm. The sealing assembly further comprised of a passageway formedin the axial stack of the plurality of diaphragm members and in fluidcommunication with the high pressure fluid region and the lower pressurefluid region. The passageway is comprised of at least one radial passageand at least one axial passage. The sealing assembly further comprisedof at least one secondary seal positioned within the passageway andconfigured to convert fluid from a high pressure axial pressure balanceto a low pressure axial pressure balance thereby reducing a radiallyinward pressure load.

In yet another embodiment, by way of example only, there is provided asealing assembly comprised of an axial stack of a plurality of diaphragmmembers, the axial stack including an upstream diaphragm and adownstream diaphragm. A plurality of finger seal plates are sandwichedbetween the upstream diaphragm and the downstream diaphragm, wherein theplurality of finger seal plates include a circumferentially continuousband portion and a plurality of uniformly spaced and angulated integralfinger portions extending radially inward from the circumferentiallycontinuous band portion and circumscribing the shaft member. The sealingassembly is further comprised of a passageway formed in the axial stackof the plurality of diaphragm members and in fluid communication withthe high pressure fluid region and the lower pressure fluid region,wherein the passageway is comprised of at least one radial passage andat least one axial passage. The sealing assembly is further comprised ofat least one wire seal piston ring positioned within the passageway andconfigured to convert fluid from a high pressure axial pressure balanceto a low pressure axial pressure balance thereby reducing a radiallyinward pressure load.

In a further embodiment, still by way of example only, there is provideda sealing assembly comprised of an axial stack of a plurality ofdiaphragm members, the axial stack including an upstream diaphragm and adownstream diaphragm. A plurality of finger seal plates are sandwichedbetween the upstream diaphragm and the downstream diaphragm. The sealingassembly is further comprised of a passageway formed in the axial stackof the plurality of diaphragm members and in fluid communication withthe high pressure fluid region and the lower pressure fluid region,wherein the passageway is comprised of at least one radial passage andat least one axial passage. The sealing assembly further comprised of awire seal piston ring positioned within the passageway and configured toconvert fluid from a high pressure axial pressure balance to a lowpressure axial pressure balance thereby reducing a radially inwardpressure load.

Other independent features and advantages of the preferred apparatuswill become apparent from the following detailed description, taken inconjunction with the accompanying drawings which illustrate, by way ofexample, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an enlarged fragmentary oblique sectional view of a pair ofreduced pressure load seal assemblies as installed in a gas turbineengine;

FIG. 2 is an enlarged fragmentary oblique sectional view of the reducedpressure load seal assembly of FIG. 1;

FIG. 3 is a cross-section view of the reduced pressure load sealassembly and secondary flow circuit of FIG. 1;

FIG. 4 is an enlarged fragmentary sectional view of a portion of theseal assembly of FIG. 1;

FIGS. 5-8 are alternative embodiments of a secondary seal in the sealassembly;

FIG. 9 is a cross-section view of the reduced pressure load sealassembly incorporating an enhanced axial pressure balance circuit; and

FIG. 10 is a fragmentary oblique sectional view of the seal assembly andsecondary flow circuits of FIG. 9.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

The following detailed description of the invention is merely exemplaryin nature and is not intended to limit the invention or the applicationand uses of the invention. Furthermore, there is no intention to bebound by any theory presented in the preceding background of theinvention or the following detailed description of the invention. Inthis regard, before proceeding with the detailed description, it is tobe appreciated that the described embodiment is not limited to use inconjunction with a specific type of engine, such as a gas turbineengine. Thus, although the description is explicitly directed toward anembodiment that is used within a gas turbine engine, it should beappreciated that it can be used within any type of apparatus requiring afluid seal between two rotatable members, including those known now orhereafter in the art.

Viewing FIGS. 1-3 in conjunction, FIG. 1 shows a sealing assembly,comprised of a first reduced pressure load seal assembly and a secondreduced pressure load seal assembly, each generally referenced 10, andconfigured as primary seals. For purposes of this disclosure, only oneof the reduced pressure load seal assemblies will be described, thesecond reduced pressure load seal assembly being substantially identicalin configuration. The reduced pressure load seal assembly 10 isillustrated as being disposed within a portion of a gas turbine engine.More specifically, the reduced pressure load seal assembly 10 isdisposed within an annular housing 18 and a rotating member of theengine such as a rotatable shaft (not shown), to provide a fluid sealtherebetween. The reduced pressure load seal assembly 10 defines a borethrough which the rotatable shaft passes. The reduced pressure load sealassembly 10 encircles and contacts the rotatable shaft to provide arotatable seal.

FIGS. 2 and 3 illustrate the reduced pressure load seal assembly 10including an axial stack of a plurality of thin annular metallicdiaphragm members 16. As best illustrated in FIG. 1, the annular housing18 defines a seal retention flange 20 to aid in the positioning of theplurality of diaphragm members 16. The plurality of diaphragm members 16each extend to and slidably engage the rotatable shaft member (notshown). As seen in FIGS. 2 and 3, each of the plurality of diaphragmmembers 16 includes an upstream diaphragm 22, a downstream diaphragm 24,and an intermediate diaphragm 26. The upstream diaphragm 22 is disposedin a high pressure fluid region 23 of the reduced pressure load sealassembly 10, while the downstream diaphragm 24 is in a low pressurefluid region 25. In addition, a plurality of finger seal plates 28 arepositioned between the upstream diaphragm 22 and the intermediatediaphragm 26, and between the downstream diaphragm 24 and theintermediate diaphragm 26. It should be understood that in analternative embodiment, the plurality of diaphragm members may notinclude an intermediate plate 26, and simply include an upstreamdiaphragm and a downstream diaphragm having the plurality of finger sealplates 28 disposed there between. Each of the plurality of diaphragmmembers 16 includes a circumferentially continuous band portion 30. Eachof the plurality of finger seal plates 28 define an integral pluralityof circumferentially uniformly arrayed finger portions 32. The fingerportions 32 are comb-like and are circumferentially spaced apart todefine a gap 34 between each finger portion 32. Typically, the gaps 34are narrower than the finger portions 32. These finger portions 32 alsoextend radially and angularly in a single circumferential direction todefine an angle. That is, the finger portions 32 extend radiallyinwardly from the circumferentially continuous band portion 30 generallylike a comb toward the shaft with a left-hand or right-handcircumferential angulation. As seen in FIG. 2, the finger portions 32have a left-hand angulation. However, in an alternate embodiment, theplurality of finger seal plates 28 may present finger portions 32 with aright-hand angulation. In their unrestrained positions, the end surfaces40 of each of the finger portions 32 cooperatively define an innerdiameter which is slightly less than the outer diameter of the rotatableshaft (not shown) positioned proximate thereto.

When the plurality of diaphragm members 16 are disposed about therotatable shaft (not shown), each finger portion 32 is deflectedslightly from its unrestrained position to lightly press an arcuate endsurface 40 against an outer surface of the rotatable shaft. As is easilyappreciated, when the rotatable shaft rotates leftwardly(counterclockwise, viewing FIG. 2), the tangential friction force at theend surface 40 provides a moment to finger portions 32 tending todecrease the perpendicular contact force between the end surface 40 andthe surface of the rotatable shaft. Thus, the rotatable shaft isrotatable counterclockwise with the finger portions 32 maintaining asmooth sliding contact with the surface of the shaft. In this particularembodiment, should the shaft rotate clockwise, the frictional force addsto the perpendicular force. However, the tangential angle of the fingerportions 32 is chosen in view of the bending strength of the fingerportions 32 and the coefficient of friction at surfaces 40 and thesurface of the rotatable shaft, so that a smooth sliding contact ismaintained at all surfaces regardless of the direction of rotation ofthe rotatable shaft.

Referring more particularly to FIG. 3, to minimize or eliminate anyhysteresis that may be present in the reduced pressure load sealassembly 10, an axial pressurization circuit creates an axial flowpassage in fluid communication with the high pressure fluid region 23,intermediate pressure region 72, and the pressure regions 71 on the lowpressure side of the plurality of diaphragm members 16. Morespecifically, as indicated by the arrows 44 in FIG. 3, when assembledand properly aligned, the plurality of diaphragm members 16 define aplurality of radial passages 70 and the plurality of axial passages 42.The plurality of axial passages 42 are formed through the plurality ofdiaphragm members 16 and provide an axial flow passage and fluidiccommunication between the high pressure fluid region 23, intermediatepressure region 72, and pressure regions 71 on the low pressure side ofthe plurality of finger seal plates 28. The inclusion of this axialpressurization circuit, and more particularly axial flow passage, whilealleviating seal hysteresis, has an undesirable effect of radiallyloading the finger portions 32 into the rotating rotatable shaft. Themagnitude of the loading is proportional to the differential pressureacross the reduced pressure load seal assembly 10. To overcome theincreased radially induced pressure load, one or more secondary seals 50are located in the reduced pressure load seal assembly 10 to convert thehigh pressure axial pressure balance to a low pressure axial pressurebalance. In operation, air flow represented by arrow 44, is restrictedto flow radially outward through the slots between the finger portions32 in the first finger seal plate 28 due to the presence of thesecondary seal 50, and subsequently between the upstream diaphragm 22and a first finger seal plate 28. The secondary seal 50 reduces the highpressure air flow 44, as it passes around the secondary seal 50. Thereduced pressure air flow 44 moves through the radial passages 70,between the upstream diaphragm 22 and a first finger plate 28, theplurality of axial passages 42 and the radial passage 70 in theintermediate diaphragm 26, exiting below the intermediate diaphragm 26.A plurality of balance pressure bleed ports 36 is provided in thereduced pressure load seal assembly 10 to permit adjustment of the axialbalance pressure. During operation, the air flow 44 repeats this process(see FIG. 3) passing through an additional secondary seal and additionalradial and axial passages, exiting through the slots in downstreamdiaphragm 24. The net axial force and radial force exerted on thereduced pressure sealing assembly 10 is greatly reduced when compared toprior art configurations that do not have pressure balancing passages orsecondary seals.

Referring still to FIGS. 2 and 3, a plurality of bleed air holes 36, ofwhich only two are illustrated, are formed in the downstream diaphragm24 and the intermediate diaphragm 26 as a serial part of the pluralityof axial passages 42. Bleed air holes 36 provide a means of adjustingthe pressure level for the axial pressure balance circuit which isdirectly related to the radially inward finger loads. In addition,illustrated is a dowel pin 38 that protrudes through the plurality ofdiaphragm members 16 and the plurality of finger seal plates 28 toprevent relative rotation of the plurality of diaphragm members 16.

Illustrated in FIG. 4 is an enlarged sectional view of a portion of thereduced pressure load seal assembly 10 of FIG. 2, and more particularlythe secondary seal 50. The secondary seal 50 has the effect of reducingthe pressure at the high pressure fluid region 23, to a lower internalpressure resulting in a reduction of the radial inward pressure load onthe plurality of finger seal plates 28, and more particularly the fingerportions 32. In the interest of minimizing cost and the additional axialloading due to the presence of the secondary seal 50, in this particularembodiment a unique wire seal piston ring design as illustrated in FIG.4 has been implemented which insures positive contact with the firstfinger seal plate 28 under low differential pressure conditions. Morespecifically, in this particular embodiment the secondary seal 50 isformed of a wire having a dimension of approximately 0.040″. Withappropriate control of the level of the balance pressure, the fingerportions 32 can be adjusted to provide any desired value of radialfinger loading against the rotating shaft. By combining the ability tocontrol the radial pressure loading with the mechanical stiffness of thefinger portions 32, design flexibility is achieved that is not currentlyavailable with brush seals and labyrinth seals when coping with largeradial displacements of the rotating shaft relative to the stationaryfinger portions 32.

Referring now to FIGS. 5 through 8, illustrated are a plurality ofalternative embodiments for the secondary seal 50. More specifically, asstated the secondary seal 50 may be any existing seal design commonlyused in main shaft face seals. Illustrated in FIG. 5 is a secondary seal60 formed by simply manufacturing the upstream diaphragm 22 and theplurality of finger seal plates 28 within close tolerances therebyreducing the flow therethrough. Illustrated in FIG. 6 is a secondaryseal 62 formed by a piston ring and spring 64. Illustrated in FIG. 7 isa secondary seal 66 formed as a “C” seal and illustrated in FIG. 8 is asecondary seal 68 formed as a tapered piston ring.

Referring now to FIGS. 9-10, illustrated is another embodiment of areduced pressure load seal assembly, referred to using reference numeral10′ to indicate an alternative embodiment. It should be noted that allcomponents of the reduced pressure load seal assembly of FIGS. 9-10 thatare similar to the components illustrated in FIGS. 1-8, are designatedwith similar numbers, having a prime added to indicate the differentembodiment.

Similar to the first described embodiment, the reduced pressure loadseal assembly 10′ is positioned in combination with a similarlyconfigured seal assembly relative to a plurality of rotating members.FIGS. 9 and 10 illustrate the reduced pressure load seal assembly 10′including a plurality of thin annular metallic diaphragm members 16′. Asseen in FIGS. 9 and 10, the plurality of diaphragm members 16′ includean upstream diaphragm 22′, a downstream diaphragm 24′, and an optionalintermediate diaphragm 26′ positioned therebetween. The upstreamdiaphragm 22′ is disposed in a high pressure fluid region 23′ of thereduced pressure load seal assembly 10′, while the downstream diaphragm24′ is in a low pressure fluid region 25′. In addition, a plurality offinger seal plates 28′ are positioned between the upstream diaphragm 22′and the intermediate diaphragm 26′, and the downstream diaphragm 24′ andthe intermediate diaphragm 26′. Similar to the first describedembodiment, each of the plurality of finger seal plates 28′ define anintegral plurality of circumferentially uniformly arrayed fingerportions 32′.

Referring to FIGS. 9 and 10, as indicated by a diagrammed flow path 44′,a plurality of axial passages 42′ and radial passages 70′ are formedthrough the plurality of diaphragm members 16′ and provide an axial flowpath and fluidic communication between the high pressure fluid region23′, intermediate pressure region 72′, and the low pressure fluid region25′. To overcome the increased radially induced pressure load, at leastone secondary seal 50′ is located in the reduced pressure load sealassembly 10′ to reduce the radial pressure loading the finger sealportions 32′ against the rotating shaft.

In contrast to the first embodiment, the reduced pressure load sealassembly 10′ further includes an enhanced axial pressure balance tofurther reduce the axial pressure load that is present. The axialpressure load results in resistance to radial displacements of thefinger portions 32′ due to friction. This may result in excessiveleakage due to the finger portions 32′ inability to follow thedisplacements of the rotating shaft during maneuvers and powerexcursions. To overcome the radial friction force induced by theincreased axial loading, a high pressure axial hydrostatic force isintroduced in a sealed cavity 90 in this particular embodiment, on adownstream 92 finger seal plate 28′. High pressure air from the highpressure fluid region 23′, or upstream side of the reduced pressure loadseal assembly 10′, is introduced directly onto the finger portions 32′of the downstream 92 finger seal plate 28′. The high pressure air flow74 is fed to the sealed cavity 90 via a fluidic pressure passage 96 andintroduced by an orifice plate 94 to the flat surfaces of the downstreamfinger portions 32′. This flow passage 96 is separated from flow passage44′ such that no fluid communication between passages can occur. Theflow in passage 96 is metered such that should the axial hydrostaticforce exceed the pressure loading, leakage is limited to an extremelysmall value. Under normal operation, the hydrostatic force is designedto be slightly less than the pressure loading such that the friction isminimized with virtually no leakage.

In order to form the plurality of diaphragm members 16 and 16′ of thedescribed embodiments, a laser cutting, wire EDM, or chemicalphotoetching process may be employed. In either case, manufacturingprocess may directly accept design information from a CAD/CAM system.The result is a reduced pressure load seal assembly which may beproduced from design parameters and information in a short time and withvery little or no specialized tooling.

While the invention has been described with reference to a preferredembodiment, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt to a particularsituation or material to the teachings of the invention withoutdeparting from the essential scope thereof. Therefore, it is intendedthat the invention not be limited to the particular embodiment disclosedas the best mode contemplated for carrying out this invention, but thatthe invention will include all embodiments falling within the scope ofthe appended claims.

1. A sealing assembly for disposition in cooperation with a bodydefining a bore and a shaft member rotatably received in the bore, andto inhibit fluid leakage between a high pressure fluid region and arelatively lower pressure fluid region, the sealing assembly comprising:at least one primary seal comprising an axial stack of a plurality ofdiaphragm members, the axial stack including an upstream diaphragm and adownstream diaphragm, a plurality of finger seal plates sandwichedbetween the upstream diaphragm and the downstream diaphragm; apassageway formed in the axial stack of the plurality of diaphragmmembers and in fluid communication with the high pressure fluid regionand the lower pressure fluid region, wherein the passageway is comprisedof at least one radial passage and at least one axial passage; and atleast one secondary seal positioned within the passageway and configuredto convert fluid from a high pressure axial pressure balance to a lowpressure axial pressure balance thereby reducing a radially inwardpressure load.
 2. The sealing assembly of claim 1, wherein the at leastone secondary seal is formed by one of a wire seal ring, by positioningthe finger seal plates in close tolerance, a piston ring and a spring, a“C” shaped seal, or a tapered piston ring.
 3. The sealing assembly ofclaim 2, wherein the wire seal ring is comprised of a 0.040″ wire. 4.The sealing assembly of claim 1, further including an intermediatediaphragm positioned between the upstream diaphragm and the downstreamdiaphragm, a first plurality of finger seal plates sandwiched betweenthe upstream diaphragm and the intermediate diaphragm, and a secondplurality of finger seal plates sandwiched between the downstreamdiaphragm and the intermediate diaphragm.
 5. The sealing assembly ofclaim 1, wherein the plurality of finger seal plates include acircumferentially continuous band portion and a plurality of uniformlyspaced and angulated integral finger portions extending radially inwardfrom the circumferentially continuous band portion and circumscribingthe shaft member.
 6. The sealing assembly of claim 5, wherein eachfinger portion being of substantially the same width and definingrespective uniform gaps between adjacent finger portions, an arcuate endedge surface of each of the finger portions sealingly and movablyengaging the shaft member
 7. The sealing assembly of claim 1, furtherincluding an annular housing defining an annular portion and a sealretention flange wherein a radially outer portion of each of theplurality of diaphragm members is received therein.
 8. The sealingassembly of claim 1, further including a high pressure hydrostatic forcein fluidic communication with the high pressure fluid region and theplurality of finger seal plates.
 9. The sealing assembly of claim 8,further including an orifice plate and a sealed cavity, wherein the highpressure hydrostatic force is fed to the sealed cavity via a fluidicpressure passage.
 10. A sealing assembly for disposition in cooperationwith a body defining a bore and a shaft member rotatably received in thebore, and to inhibit fluid leakage between a high pressure fluid regionand a relatively lower pressure fluid region, the sealing assemblycomprising: an axial stack of a plurality of diaphragm members, theaxial stack including an upstream diaphragm and a downstream diaphragm,a plurality of finger seal plates sandwiched between the upstreamdiaphragm and the downstream diaphragm, wherein the plurality of fingerseal plates include a circumferentially continuous band portion and aplurality of uniformly spaced and angulated integral finger portionsextending radially inward from the circumferentially continuous bandportion and circumscribing the shaft member; a passageway formed in theaxial stack of the plurality of diaphragm members and in fluidcommunication with the high pressure fluid region and the lower pressurefluid region, wherein the passageway is comprised of at least one radialpassage and at least one axial passage; and at least one secondary sealpositioned within the passageway and configured to convert fluid from ahigh pressure axial pressure balance to a low pressure axial pressurebalance thereby reducing a radially inward pressure load.
 11. Thesealing assembly of claim 10, wherein at least one secondary seal is awire seal piston ring is comprised of a 0.040″ wire.
 12. The sealingassembly of claim 10, further including an intermediate diaphragmpositioned between the upstream diaphragm and the downstream diaphragm,a first plurality of finger seal plates sandwiched between the upstreamdiaphragm and the intermediate diaphragm, and a second plurality offinger seal plates sandwiched between the downstream diaphragm and theintermediate diaphragm.
 13. The sealing assembly of claim 10, furtherincluding an annular housing defining an annular portion and a sealretention flange wherein a radially outer portion of each of theplurality of diaphragm members is received therein.
 14. The sealingassembly of claim 10, further including a high pressure hydrostaticforce in fluidic communication with the high pressure fluid region andat least one of the plurality of finger seal plates.
 15. The sealingassembly of claim 14, further including an orifice plate and a sealedcavity, wherein the high pressure hydrostatic force is fed to the sealedcavity via a fluidic pressure passage.
 16. A sealing assembly fordisposition in cooperation with a body defining a bore and a shaftmember rotatably received in the bore, and to inhibit fluid leakagebetween a high pressure fluid region and a relatively lower pressurefluid region, the sealing assembly comprising: an axial stack of aplurality of diaphragm members, the axial stack including an upstreamdiaphragm and a downstream diaphragm, a plurality of finger seal platessandwiched between the upstream diaphragm and the downstream diaphragm;a passageway formed in the axial stack of the plurality of diaphragmmembers and in fluid communication with the high pressure fluid regionand the lower pressure fluid region, wherein the passageway is comprisedof at least one radial passage and at least one axial passage; and awire seal piston ring positioned within the passageway and configured toconvert fluid from a high pressure axial pressure balance to a lowpressure axial pressure balance thereby reducing a radially inwardpressure load.
 17. The sealing assembly of claim 16, wherein the wireseal piston ring is comprised of a 0.040″ wire.
 18. The sealing assemblyof claim 16, wherein the plurality of finger seal plates include acircumferentially continuous band portion and a plurality of uniformlyspaced and angulated integral finger portions extending radially inwardfrom the circumferentially continuous band portion and circumscribingthe shaft member.
 19. The sealing assembly of claim 16, furtherincluding a high pressure hydrostatic force in fluidic communicationwith the high pressure fluid region and the plurality of finger sealplates.
 20. The sealing assembly of claim 19, further including anorifice plate and a sealed cavity, wherein the high pressure hydrostaticforce is fed to the sealed cavity via a fluidic pressure passage.